The ground wire for the strings/hardware was attached to the base of one of the holes for holding the pole pieces for the stop bar tail piece. And obviously via this path the hardware and strings on the guitar were earthed.
The guy who installed the Bigsby overlooked this, so the hardware and strings are no longer earthed seeing as the stop bar tailpiece is no longer present.
So, what is the best way to go about earthing a Bigsby in this situation?
You can just ground the bridge the same way the stop bar was grounded. That should take care of it because the strings touch the bridge and the bigsby too.
I stripped and coiled up some bell wire and put it down the posthole so it is in contact with the metal in a number of places. Then I wrapped the wire around the Bigsby a couple of times and sealed the ends together with a bit of solder.
Seems to work fine, and seeing as it won't be moved at all it will continue to do so hopefully.